package Stack;

import java.util.Stack;

public class MinStack {

    public Stack<Integer> stack;
    public Stack<Integer> minStack;

    public MinStack(){
        stack = new Stack<>();
        minStack = new Stack<>();
    }

    public void push(int val){
        stack.push(val);
        if(minStack.empty()){
            minStack.push(val);
        }else{
            int peekVal = minStack.peek();
            if(val <= peekVal){
                minStack.push(val);
            }
        }
    }

    public void pop(){
        if(stack.empty()){
            return;
        }
        int popVal = stack.pop();
        if(popVal == minStack.peek()){
            minStack.pop();
        }
    }

    public int top(){
        if (stack.empty()){
            return -1;
        }
        return stack.peek();
    }

    public int getMin(){
        if(minStack.empty()){
            return -1;
        }
        return minStack.peek();
    }
}
